sceneIndex.h

//
// Copyright 2026 Pixar
//
// Licensed under the terms set forth in the LICENSE.txt file available at
// https://openusd.org/license.
//
#ifndef PXR_USD_IMAGING_USD_IMAGING_SCENE_INDEX_H
#define PXR_USD_IMAGING_USD_IMAGING_SCENE_INDEX_H
 
#include "pxr/pxr.h"
 
#include "pxr/usd/usd/timeCode.h"
 
#include "pxr/usdImaging/usdImaging/api.h"
 
#include "pxr/imaging/hd/filteringSceneIndex.h"
#include "pxr/imaging/hd/sceneIndex.h"
 
PXR_NAMESPACE_OPEN_SCOPE
 
using UsdImagingSceneIndexAppendCallback =
    std::function<
        HdSceneIndexBaseRefPtr(HdSceneIndexBaseRefPtr const &)>;
 
struct UsdImagingSceneIndices;
TF_DECLARE_REF_PTRS(HdNoticeBatchingSceneIndex);
TF_DECLARE_REF_PTRS(UsdStage);
TF_DECLARE_REF_PTRS(UsdImagingStageSceneIndex);
TF_DECLARE_REF_PTRS(UsdImagingSelectionSceneIndex);
TF_DECLARE_REF_PTRS(UsdImagingSceneIndex);
 
class UsdImagingSceneIndex
            : public HdSceneIndexBase, public HdEncapsulatingSceneIndexBase
{
public:
    static UsdImagingSceneIndexRefPtr New(
            HdContainerDataSourceHandle const &inputArgs,
            const UsdImagingSceneIndexAppendCallback &
                overridesSceneIndexCallback) {
        return TfCreateRefPtr(
            new UsdImagingSceneIndex(
                inputArgs, overridesSceneIndexCallback));
    }
 
    USDIMAGING_API
    ~UsdImagingSceneIndex();
 
    // ------------------------------------------------------------------------
    // (Encapsulating) Scene index API
 
    USDIMAGING_API
    HdSceneIndexPrim GetPrim(const SdfPath & primPath) const override;
 
    USDIMAGING_API
    SdfPathVector GetChildPrimPaths(const SdfPath & primPath) const override;
 
    USDIMAGING_API
    HdSceneIndexBaseRefPtrVector GetEncapsulatedScenes() const override;
 
    // ------------------------------------------------------------------------
    // App-facing API
 
    // Set the USD stage to pull data from. Note that this will delete all
    // scene index prims and reset stage global data.
    USDIMAGING_API
    void SetStage(UsdStageRefPtr stage);
 
    // Set the time, and call PrimsDirtied for any time-varying attributes.
    //
    // PrimsDirtied is only called if the time is different from the last call
    // or forceDirtyingTimeDeps is true.
    USDIMAGING_API
    void SetTime(UsdTimeCode time, bool forceDirtyingTimeDeps = false);
 
    // Return the current time.
    USDIMAGING_API
    UsdTimeCode GetTime() const;
 
    // Apply queued stage edits to imaging scene.
    // If the USD stage is edited while the scene index is pulling from it,
    // those edits get queued and deferred.  Calling ApplyPendingUpdates will
    // turn resync requests into PrimsAdded/PrimsRemoved, and property changes
    // into PrimsDirtied.
    USDIMAGING_API
    void ApplyPendingUpdates();
 
    USDIMAGING_API
    void AddSelection(const SdfPath &path);
 
    USDIMAGING_API
    void ClearSelection();
 
    const HdNoticeBatchingSceneIndexRefPtr &
    GetPostInstancingNoticeBatchingSceneIndex() const {
        return _postInstancingNoticeBatchingSceneIndex;
    }
 
private:
    class _Observer : public HdSceneIndexObserver
    {
    public:
        _Observer(UsdImagingSceneIndex *owner)
          : _owner(owner) {}
 
        void PrimsAdded(
            const HdSceneIndexBase &sender,
            const AddedPrimEntries &entries) override
        {
            _owner->_SendPrimsAdded(entries);
        }
 
        void PrimsRemoved(
            const HdSceneIndexBase &sender,
            const RemovedPrimEntries &entries) override
        {
            _owner->_SendPrimsRemoved(entries);
        }
 
        void PrimsDirtied(
            const HdSceneIndexBase &sender,
            const DirtiedPrimEntries &entries) override
        {
            _owner->_SendPrimsDirtied(entries);
        }
 
        void PrimsRenamed(
            const HdSceneIndexBase &sender,
            const RenamedPrimEntries &entries) override
        {
            _owner->_SendPrimsRenamed(entries);
        }
    private:
        UsdImagingSceneIndex * const _owner;
    };
 
    USDIMAGING_API
    UsdImagingSceneIndex(
        HdContainerDataSourceHandle const &inputArgs,
        const UsdImagingSceneIndexAppendCallback &overridesSceneIndexCallback);
 
    USDIMAGING_API
    UsdImagingSceneIndex(
        const UsdImagingSceneIndices &sceneIndices);
 
    UsdImagingStageSceneIndexRefPtr _stageSceneIndex;
    HdNoticeBatchingSceneIndexRefPtr _postInstancingNoticeBatchingSceneIndex;
    UsdImagingSelectionSceneIndexRefPtr _selectionSceneIndex;
    HdSceneIndexBaseRefPtr _finalSceneIndex;
 
    _Observer _observer;
};
 
PXR_NAMESPACE_CLOSE_SCOPE
 
#endif